Area Forecast Discussion
Issued by NWS Charleston, SC
FXUS62 KCHS 250955
Area Forecast Discussion
National Weather Service Charleston SC
555 AM EDT Tue Apr 25 2017
Low pressure will move away from the area today while high
pressure builds in. A weak disturbance will affect the area
Thursday night, then high pressure will prevail Friday through
the weekend. A cold front will affect the area Monday and Monday
.NEAR TERM /THROUGH TONIGHT/...
Today: The deep mid/upper level low will start off the day
situated near the North Carolina/South Carolina state line along
the coast. This feature will then steadily ride to the
northeast and further from the forecast area through the day. At
the surface, an area of low pressure over central North
Carolina will lift to the northeast as well. This setup will
leave the forecast area in a transition zone for the day with
high pressure well to the south attempting to build in. We may
still see showers developing under the mid/upper level low in
the morning, mainly impacting locations across eastern Berkeley
and Charleston counties. PoP`s are in the 20-30 percent range as
the coverage of showers will be limited thanks to the waning
influence of the mid/upper level low. Instead, the main impact
will be lingering low level stratus that will impact much of
southeast South Carolina well into the afternoon. Southeast
Georgia will clear out first and should see plenty of sunshine
in the afternoon. High temperatures are expected to range from
the low 80s closer to the Altamaha, to the mid 70s near the
Tonight: A very quiet night will be on tap as any remaining low
level moisture gets stripped out behind the departing surface
low. The forecast is dry with mostly clear skies and lows in the
upper 50s to low 60s.
.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
Deep layered ridging Wednesday into Thursday will support high
temps in the middle 80s most areas. A weak upper disturbance
will brush past the western areas late Thursday into Thursday
night. Atmospheric moisture will increase enough to support at
least isolated showers and thunderstorms over our inland zones,
possibly the result of a decaying convective cluster late
Thursday afternoon into the evening.
A strengthening low/mid level ridge on Friday with low-level
warm advection and mostly sunny skies will help push high temps
into the upper 80s to lower 90s.
.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
Above normal temperatures and mainly dry weather will persist
into Sunday. An upper trough approaches early next week with a
cold front expected to push through Monday and Monday night,
bringing scattered showers/storms.
.AVIATION /10Z TUESDAY THROUGH SATURDAY/...
At KCHS, IFR ceilings have settled in and should remain through
much of the morning. By mid to late morning, IFR ceilings will
lift to MVFR. MVFR ceilings will then likely linger into the
afternoon before VFR returns late in the day.
At KSAV, confidence is lower that IFR conditions settle in, and
if they do it should be a shorter time period. Still think IFR
ceilings will occur, but only carry them from 10-13z. KSAV will
scatter out sooner and VFR conditions will prevail by late
morning or around noon.
Extended Aviation Outlook: No significant concerns.
Today: Flow around the departing area of low pressure will help
to keep westerly flow going through the morning before it turns
more southwesterly in the afternoon. Wind speeds in the morning
will be in the 15-20 knot range, diminishing to 10-15 knots in
the afternoon. Seas will gradually decrease through the day,
starting off 3-5 feet in the morning with 4-6 feet across the
outer waters. Then later in the day, expect 2-4 feet out to 20
nm and 4-5 feet beyond.
Tonight: The prevailing flow will remain westerly though the
pressure gradient will decrease significantly. Speeds will be on
the decline, becoming no more than 10 knots by sunrise
Wednesday. Seas will generally range 2-4 feet.
Mainly southerly flow will prevail Wednesday into the weekend
as Atlantic high pressure holds firm. The strongest winds will
occur in the evening over the nearshore waters where low-level
jetting occurs. Additionally, the seabreeze will be fairly
potent each afternoon along the coast.
Shallow coastal flooding possible with the evening high tides
through Thursday due to the spring tides and possible additional
MARINE...Small Craft Advisory until 2 PM EDT this afternoon for AMZ374.